/* * Driver for 8250/16550-type serial ports * * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. * * Copyright (C) 2001 Russell King. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * A note about mapbase / membase * * mapbase is the physical address of the IO port. Currently, we don't * support this very well, and it may well be dropped from this driver * in future. As such, mapbase should be NULL. * * membase is an 'ioremapped' cookie. This is compatible with the old * serial.c driver, and is currently the preferred form. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(CONFIG_SERIAL_AU1X00_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) #define SUPPORT_SYSRQ #endif #include #include "8250.h" /* * Debugging. */ #if 0 #define DEBUG_AUTOCONF(fmt...) printk(fmt) #else #define DEBUG_AUTOCONF(fmt...) do { } while (0) #endif #if 0 #define DEBUG_INTR(fmt...) printk(fmt) #else #define DEBUG_INTR(fmt...) do { } while (0) #endif #define PASS_LIMIT 256 /* * We default to IRQ0 for the "no irq" hack. Some * machine types want others as well - they're free * to redefine this in their header file. */ #define is_real_interrupt(irq) ((irq) != 0) static struct old_serial_port old_serial_port[] = { { .baud_base = 0, .iomem_base = (u8 *)UART0_ADDR, .irq = AU1000_UART0_INT, .flags = STD_COM_FLAGS, .iomem_reg_shift = 2, }, { .baud_base = 0, .iomem_base = (u8 *)UART1_ADDR, .irq = AU1000_UART1_INT, .flags = STD_COM_FLAGS, .iomem_reg_shift = 2 }, { .baud_base = 0, .iomem_base = (u8 *)UART2_ADDR, .irq = AU1000_UART2_INT, .flags = STD_COM_FLAGS, .iomem_reg_shift = 2 }, { .baud_base = 0, .iomem_base = (u8 *)UART3_ADDR, .irq = AU1000_UART3_INT, .flags = STD_COM_FLAGS, .iomem_reg_shift = 2 } }; #define UART_NR ARRAY_SIZE(old_serial_port) struct uart_8250_port { struct uart_port port; struct timer_list timer; /* "no irq" timer */ struct list_head list; /* ports on this IRQ */ unsigned short rev; unsigned char acr; unsigned char ier; unsigned char lcr; unsigned char mcr_mask; /* mask of user bits */ unsigned char mcr_force; /* mask of forced bits */ unsigned char lsr_break_flag; /* * We provide a per-port pm hook. */ void (*pm)(struct uart_port *port, unsigned int state, unsigned int old); }; struct irq_info { spinlock_t lock; struct list_head *head; }; static struct irq_info irq_lists[NR_IRQS]; /* * Here we define the default xmit fifo size used for each type of UART. */ static const struct serial_uart_config uart_config[PORT_MAX_8250+1] = { { "unknown", 1, 0 }, { "8250", 1, 0 }, { "16450", 1, 0 }, { "16550", 1, 0 }, /* PORT_16550A */ { "AU1X00_UART",16, UART_CLEAR_FIFO | UART_USE_FIFO }, }; static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset) { return au_readl((unsigned long)up->port.membase + offset); } static _INLINE_ void serial_out(struct uart_8250_port *up, int offset, int value) { au_writel(value, (unsigned long)up->port.membase + offset); } #define serial_inp(up, offset) serial_in(up, offset) #define serial_outp(up, offset, value) serial_out(up, offset, value) /* * This routine is called by rs_init() to initialize a specific serial * port. It determines what type of UART chip this serial port is * using: 8250, 16450, 16550, 16550A. The important question is * whether or not this UART is a 16550A or not, since this will * determine whether or not we can use its FIFO features or not. */ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags) { unsigned char save_lcr, save_mcr; unsigned long flags; if (!up->port.iobase && !up->port.mapbase && !up->port.membase) return; DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%08lx): ", up->port.line, up->port.iobase, up->port.membase); /* * We really do need global IRQs disabled here - we're going to * be frobbing the chips IRQ enable register to see if it exists. */ spin_lock_irqsave(&up->port.lock, flags); // save_flags(flags); cli(); save_mcr = serial_in(up, UART_MCR); save_lcr = serial_in(up, UART_LCR); up->port.type = PORT_16550A; serial_outp(up, UART_LCR, save_lcr); up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size; if (up->port.type == PORT_UNKNOWN) goto out; /* * Reset the UART. */ serial_outp(up, UART_MCR, save_mcr); serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)); serial_outp(up, UART_FCR, 0); (void)serial_in(up, UART_RX); serial_outp(up, UART_IER, 0); out: spin_unlock_irqrestore(&up->port.lock, flags); // restore_flags(flags); DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name); } static void serial8250_stop_tx(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; if (up->ier & UART_IER_THRI) { up->ier &= ~UART_IER_THRI; serial_out(up, UART_IER, up->ier); } } static void serial8250_start_tx(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; if (!(up->ier & UART_IER_THRI)) { up->ier |= UART_IER_THRI; serial_out(up, UART_IER, up->ier); } } static void serial8250_stop_rx(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; up->ier &= ~UART_IER_RLSI; up->port.read_status_mask &= ~UART_LSR_DR; serial_out(up, UART_IER, up->ier); } static void serial8250_enable_ms(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; up->ier |= UART_IER_MSI; serial_out(up, UART_IER, up->ier); } static _INLINE_ void receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs) { struct tty_struct *tty = up->port.info->tty; unsigned char ch; int max_count = 256; do { if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) { tty->flip.work.func((void *)tty); if (tty->flip.count >= TTY_FLIPBUF_SIZE) return; // if TTY_DONT_FLIP is set } ch = serial_inp(up, UART_RX); *tty->flip.char_buf_ptr = ch; *tty->flip.flag_buf_ptr = TTY_NORMAL; up->port.icount.rx++; if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE | UART_LSR_FE | UART_LSR_OE))) { /* * For statistics only */ if (*status & UART_LSR_BI) { *status &= ~(UART_LSR_FE | UART_LSR_PE); up->port.icount.brk++; /* * We do the SysRQ and SAK checking * here because otherwise the break * may get masked by ignore_status_mask * or read_status_mask. */ if (uart_handle_break(&up->port)) goto ignore_char; } else if (*status & UART_LSR_PE) up->port.icount.parity++; else if (*status & UART_LSR_FE) up->port.icount.frame++; if (*status & UART_LSR_OE) up->port.icount.overrun++; /* * Mask off conditions which should be ingored. */ *status &= up->port.read_status_mask; #ifdef CONFIG_SERIAL_AU1X00_CONSOLE if (up->port.line == up->port.cons->index) { /* Recover the break flag from console xmit */ *status |= up->lsr_break_flag; up->lsr_break_flag = 0; } #endif if (*status & UART_LSR_BI) { DEBUG_INTR("handling break...."); *tty->flip.flag_buf_ptr = TTY_BREAK; } else if (*status & UART_LSR_PE) *tty->flip.flag_buf_ptr = TTY_PARITY; else if (*status & UART_LSR_FE) *tty->flip.flag_buf_ptr = TTY_FRAME; } if (uart_handle_sysrq_char(&up->port, ch, regs)) goto ignore_char; if ((*status & up->port.ignore_status_mask) == 0) { tty->flip.flag_buf_ptr++; tty->flip.char_buf_ptr++; tty->flip.count++; } if ((*status & UART_LSR_OE) && tty->flip.count < TTY_FLIPBUF_SIZE) { /* * Overrun is special, since it's reported * immediately, and doesn't affect the current * character. */ *tty->flip.flag_buf_ptr = TTY_OVERRUN; tty->flip.flag_buf_ptr++; tty->flip.char_buf_ptr++; tty->flip.count++; } ignore_char: *status = serial_inp(up, UART_LSR); } while ((*status & UART_LSR_DR) && (max_count-- > 0)); spin_unlock(&up->port.lock); tty_flip_buffer_push(tty); spin_lock(&up->port.lock); } static _INLINE_ void transmit_chars(struct uart_8250_port *up) { struct circ_buf *xmit = &up->port.info->xmit; int count; if (up->port.x_char) { serial_outp(up, UART_TX, up->port.x_char); up->port.icount.tx++; up->port.x_char = 0; return; } if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { serial8250_stop_tx(&up->port); return; } count = up->port.fifosize; do { serial_out(up, UART_TX, xmit->buf[xmit->tail]); xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); up->port.icount.tx++; if (uart_circ_empty(xmit)) break; } while (--count > 0); if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&up->port); DEBUG_INTR("THRE..."); if (uart_circ_empty(xmit)) serial8250_stop_tx(&up->port); } static _INLINE_ void check_modem_status(struct uart_8250_port *up) { int status; status = serial_in(up, UART_MSR); if ((status & UART_MSR_ANY_DELTA) == 0) return; if (status & UART_MSR_TERI) up->port.icount.rng++; if (status & UART_MSR_DDSR) up->port.icount.dsr++; if (status & UART_MSR_DDCD) uart_handle_dcd_change(&up->port, status & UART_MSR_DCD); if (status & UART_MSR_DCTS) uart_handle_cts_change(&up->port, status & UART_MSR_CTS); wake_up_interruptible(&up->port.info->delta_msr_wait); } /* * This handles the interrupt from one port. */ static inline void serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs) { unsigned int status = serial_inp(up, UART_LSR); DEBUG_INTR("status = %x...", status); if (status & UART_LSR_DR) receive_chars(up, &status, regs); check_modem_status(up); if (status & UART_LSR_THRE) transmit_chars(up); } /* * This is the serial driver's interrupt routine. * * Arjan thinks the old way was overly complex, so it got simplified. * Alan disagrees, saying that need the complexity to handle the weird * nature of ISA shared interrupts. (This is a special exception.) * * In order to handle ISA shared interrupts properly, we need to check * that all ports have been serviced, and therefore the ISA interrupt * line has been de-asserted. * * This means we need to loop through all ports. checking that they * don't have an interrupt pending. */ static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *regs) { struct irq_info *i = dev_id; struct list_head *l, *end = NULL; int pass_counter = 0; DEBUG_INTR("serial8250_interrupt(%d)...", irq); spin_lock(&i->lock); l = i->head; do { struct uart_8250_port *up; unsigned int iir; up = list_entry(l, struct uart_8250_port, list); iir = serial_in(up, UART_IIR); if (!(iir & UART_IIR_NO_INT)) { spin_lock(&up->port.lock); serial8250_handle_port(up, regs); spin_unlock(&up->port.lock); end = NULL; } else if (end == NULL) end = l; l = l->next; if (l == i->head && pass_counter++ > PASS_LIMIT) { /* If we hit this, we're dead. */ printk(KERN_ERR "serial8250: too much work for " "irq%d\n", irq); break; } } while (l != end); spin_unlock(&i->lock); DEBUG_INTR("end.\n"); /* FIXME! Was it really ours? */ return IRQ_HANDLED; } /* * To support ISA shared interrupts, we need to have one interrupt * handler that ensures that the IRQ line has been deasserted * before returning. Failing to do this will result in the IRQ * line being stuck active, and, since ISA irqs are edge triggered, * no more IRQs will be seen. */ static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up) { spin_lock_irq(&i->lock); if (!list_empty(i->head)) { if (i->head == &up->list) i->head = i->head->next; list_del(&up->list); } else { BUG_ON(i->head != &up->list); i->head = NULL; } spin_unlock_irq(&i->lock); } static int serial_link_irq_chain(struct uart_8250_port *up) { struct irq_info *i = irq_lists + up->port.irq; int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0; spin_lock_irq(&i->lock); if (i->head) { list_add(&up->list, i->head); spin_unlock_irq(&i->lock); ret = 0; } else { INIT_LIST_HEAD(&up->list); i->head = &up->list; spin_unlock_irq(&i->lock); ret = request_irq(up->port.irq, serial8250_interrupt, irq_flags, "serial", i); if (ret < 0) serial_do_unlink(i, up); } return ret; } static void serial_unlink_irq_chain(struct uart_8250_port *up) { struct irq_info *i = irq_lists + up->port.irq; BUG_ON(i->head == NULL); if (list_empty(i->head)) free_irq(up->port.irq, i); serial_do_unlink(i, up); } /* * This function is used to handle ports that do not have an * interrupt. This doesn't work very well for 16450's, but gives * barely passable results for a 16550A. (Although at the expense * of much CPU overhead). */ static void serial8250_timeout(unsigned long data) { struct uart_8250_port *up = (struct uart_8250_port *)data; unsigned int timeout; unsigned int iir; iir = serial_in(up, UART_IIR); if (!(iir & UART_IIR_NO_INT)) { spin_lock(&up->port.lock); serial8250_handle_port(up, NULL); spin_unlock(&up->port.lock); } timeout = up->port.timeout; timeout = timeout > 6 ? (timeout / 2 - 2) : 1; mod_timer(&up->timer, jiffies + timeout); } static unsigned int serial8250_tx_empty(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned long flags; unsigned int ret; spin_lock_irqsave(&up->port.lock, flags); ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0; spin_unlock_irqrestore(&up->port.lock, flags); return ret; } static unsigned int serial8250_get_mctrl(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned char status; unsigned int ret; status = serial_in(up, UART_MSR); ret = 0; if (status & UART_MSR_DCD) ret |= TIOCM_CAR; if (status & UART_MSR_RI) ret |= TIOCM_RNG; if (status & UART_MSR_DSR) ret |= TIOCM_DSR; if (status & UART_MSR_CTS) ret |= TIOCM_CTS; return ret; } static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned char mcr = 0; if (mctrl & TIOCM_RTS) mcr |= UART_MCR_RTS; if (mctrl & TIOCM_DTR) mcr |= UART_MCR_DTR; if (mctrl & TIOCM_OUT1) mcr |= UART_MCR_OUT1; if (mctrl & TIOCM_OUT2) mcr |= UART_MCR_OUT2; if (mctrl & TIOCM_LOOP) mcr |= UART_MCR_LOOP; mcr = (mcr & up->mcr_mask) | up->mcr_force; serial_out(up, UART_MCR, mcr); } static void serial8250_break_ctl(struct uart_port *port, int break_state) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned long flags; spin_lock_irqsave(&up->port.lock, flags); if (break_state == -1) up->lcr |= UART_LCR_SBC; else up->lcr &= ~UART_LCR_SBC; serial_out(up, UART_LCR, up->lcr); spin_unlock_irqrestore(&up->port.lock, flags); } static int serial8250_startup(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned long flags; int retval; /* * Clear the FIFO buffers and disable them. * (they will be reeanbled in set_termios()) */ if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) { serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO); serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); serial_outp(up, UART_FCR, 0); } /* * Clear the interrupt registers. */ (void) serial_inp(up, UART_LSR); (void) serial_inp(up, UART_RX); (void) serial_inp(up, UART_IIR); (void) serial_inp(up, UART_MSR); /* * At this point, there's no way the LSR could still be 0xff; * if it is, then bail out, because there's likely no UART * here. */ if (!(up->port.flags & UPF_BUGGY_UART) && (serial_inp(up, UART_LSR) == 0xff)) { printk("ttyS%d: LSR safety check engaged!\n", up->port.line); return -ENODEV; } retval = serial_link_irq_chain(up); if (retval) return retval; /* * Now, initialize the UART */ serial_outp(up, UART_LCR, UART_LCR_WLEN8); spin_lock_irqsave(&up->port.lock, flags); if (up->port.flags & UPF_FOURPORT) { if (!is_real_interrupt(up->port.irq)) up->port.mctrl |= TIOCM_OUT1; } else /* * Most PC uarts need OUT2 raised to enable interrupts. */ if (is_real_interrupt(up->port.irq)) up->port.mctrl |= TIOCM_OUT2; serial8250_set_mctrl(&up->port, up->port.mctrl); spin_unlock_irqrestore(&up->port.lock, flags); /* * Finally, enable interrupts. Note: Modem status interrupts * are set via set_termios(), which will be occurring imminently * anyway, so we don't enable them here. */ up->ier = UART_IER_RLSI | UART_IER_RDI; serial_outp(up, UART_IER, up->ier); if (up->port.flags & UPF_FOURPORT) { unsigned int icp; /* * Enable interrupts on the AST Fourport board */ icp = (up->port.iobase & 0xfe0) | 0x01f; outb_p(0x80, icp); (void) inb_p(icp); } /* * And clear the interrupt registers again for luck. */ (void) serial_inp(up, UART_LSR); (void) serial_inp(up, UART_RX); (void) serial_inp(up, UART_IIR); (void) serial_inp(up, UART_MSR); return 0; } static void serial8250_shutdown(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned long flags; /* * Disable interrupts from this port */ up->ier = 0; serial_outp(up, UART_IER, 0); spin_lock_irqsave(&up->port.lock, flags); if (up->port.flags & UPF_FOURPORT) { /* reset interrupts on the AST Fourport board */ inb((up->port.iobase & 0xfe0) | 0x1f); up->port.mctrl |= TIOCM_OUT1; } else up->port.mctrl &= ~TIOCM_OUT2; serial8250_set_mctrl(&up->port, up->port.mctrl); spin_unlock_irqrestore(&up->port.lock, flags); /* * Disable break condition and FIFOs */ serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC); serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); serial_outp(up, UART_FCR, 0); /* * Read data port to reset things, and then unlink from * the IRQ chain. */ (void) serial_in(up, UART_RX); if (!is_real_interrupt(up->port.irq)) del_timer_sync(&up->timer); else serial_unlink_irq_chain(up); } static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud) { unsigned int quot; /* * Handle magic divisors for baud rates above baud_base on * SMSC SuperIO chips. */ if ((port->flags & UPF_MAGIC_MULTIPLIER) && baud == (port->uartclk/4)) quot = 0x8001; else if ((port->flags & UPF_MAGIC_MULTIPLIER) && baud == (port->uartclk/8)) quot = 0x8002; else quot = uart_get_divisor(port, baud); return quot; } static void serial8250_set_termios(struct uart_port *port, struct termios *termios, struct termios *old) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned char cval, fcr = 0; unsigned long flags; unsigned int baud, quot; switch (termios->c_cflag & CSIZE) { case CS5: cval = UART_LCR_WLEN5; break; case CS6: cval = UART_LCR_WLEN6; break; case CS7: cval = UART_LCR_WLEN7; break; default: case CS8: cval = UART_LCR_WLEN8; break; } if (termios->c_cflag & CSTOPB) cval |= UART_LCR_STOP; if (termios->c_cflag & PARENB) cval |= UART_LCR_PARITY; if (!(termios->c_cflag & PARODD)) cval |= UART_LCR_EPAR; #ifdef CMSPAR if (termios->c_cflag & CMSPAR) cval |= UART_LCR_SPAR; #endif /* * Ask the core to calculate the divisor for us. */ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); quot = serial8250_get_divisor(port, baud); quot = 0x35; /* FIXME */ /* * Work around a bug in the Oxford Semiconductor 952 rev B * chip which causes it to seriously miscalculate baud rates * when DLL is 0. */ if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 && up->rev == 0x5201) quot ++; if (uart_config[up->port.type].flags & UART_USE_FIFO) { if (baud < 2400) fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_1; else fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_8; } /* * Ok, we're now changing the port state. Do it with * interrupts disabled. */ spin_lock_irqsave(&up->port.lock, flags); /* * Update the per-port timeout. */ uart_update_timeout(port, termios->c_cflag, baud); up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; if (termios->c_iflag & INPCK) up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE; if (termios->c_iflag & (BRKINT | PARMRK)) up->port.read_status_mask |= UART_LSR_BI; /* * Characteres to ignore */ up->port.ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; if (termios->c_iflag & IGNBRK) { up->port.ignore_status_mask |= UART_LSR_BI; /* * If we're ignoring parity and break indicators, * ignore overruns too (for real raw support). */ if (termios->c_iflag & IGNPAR) up->port.ignore_status_mask |= UART_LSR_OE; } /* * ignore all characters if CREAD is not set */ if ((termios->c_cflag & CREAD) == 0) up->port.ignore_status_mask |= UART_LSR_DR; /* * CTS flow control flag and modem status interrupts */ up->ier &= ~UART_IER_MSI; if (UART_ENABLE_MS(&up->port, termios->c_cflag)) up->ier |= UART_IER_MSI; serial_out(up, UART_IER, up->ier); serial_outp(up, 0x28, quot & 0xffff); up->lcr = cval; /* Save LCR */ if (up->port.type != PORT_16750) { if (fcr & UART_FCR_ENABLE_FIFO) { /* emulated UARTs (Lucent Venus 167x) need two steps */ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO); } serial_outp(up, UART_FCR, fcr); /* set fcr */ } spin_unlock_irqrestore(&up->port.lock, flags); } static void serial8250_pm(struct uart_port *port, unsigned int state, unsigned int oldstate) { struct uart_8250_port *up = (struct uart_8250_port *)port; if (state) { /* sleep */ if (up->pm) up->pm(port, state, oldstate); } else { /* wake */ if (up->pm) up->pm(port, state, oldstate); } } /* * Resource handling. This is complicated by the fact that resources * depend on the port type. Maybe we should be claiming the standard * 8250 ports, and then trying to get other resources as necessary? */ static int serial8250_request_std_resource(struct uart_8250_port *up, struct resource **res) { unsigned int size = 8 << up->port.regshift; int ret = 0; switch (up->port.iotype) { case SERIAL_IO_MEM: if (up->port.mapbase) { *res = request_mem_region(up->port.mapbase, size, "serial"); if (!*res) ret = -EBUSY; } break; case SERIAL_IO_HUB6: case SERIAL_IO_PORT: *res = request_region(up->port.iobase, size, "serial"); if (!*res) ret = -EBUSY; break; } return ret; } static void serial8250_release_port(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned long start, offset = 0, size = 0; size <<= up->port.regshift; switch (up->port.iotype) { case SERIAL_IO_MEM: if (up->port.mapbase) { /* * Unmap the area. */ iounmap(up->port.membase); up->port.membase = NULL; start = up->port.mapbase; if (size) release_mem_region(start + offset, size); release_mem_region(start, 8 << up->port.regshift); } break; case SERIAL_IO_HUB6: case SERIAL_IO_PORT: start = up->port.iobase; if (size) release_region(start + offset, size); release_region(start + offset, 8 << up->port.regshift); break; default: break; } } static int serial8250_request_port(struct uart_port *port) { struct uart_8250_port *up = (struct uart_8250_port *)port; struct resource *res = NULL, *res_rsa = NULL; int ret = 0; ret = serial8250_request_std_resource(up, &res); /* * If we have a mapbase, then request that as well. */ if (ret == 0 && up->port.flags & UPF_IOREMAP) { int size = res->end - res->start + 1; up->port.membase = ioremap(up->port.mapbase, size); if (!up->port.membase) ret = -ENOMEM; } if (ret < 0) { if (res_rsa) release_resource(res_rsa); if (res) release_resource(res); } return ret; } static void serial8250_config_port(struct uart_port *port, int flags) { struct uart_8250_port *up = (struct uart_8250_port *)port; struct resource *res_std = NULL, *res_rsa = NULL; int probeflags = PROBE_ANY; probeflags &= ~PROBE_RSA; if (flags & UART_CONFIG_TYPE) autoconfig(up, probeflags); /* * If the port wasn't an RSA port, release the resource. */ if (up->port.type != PORT_RSA && res_rsa) release_resource(res_rsa); if (up->port.type == PORT_UNKNOWN && res_std) release_resource(res_std); } static int serial8250_verify_port(struct uart_port *port, struct serial_struct *ser) { if (ser->irq >= NR_IRQS || ser->irq < 0 || ser->baud_base < 9600 || ser->type < PORT_UNKNOWN || ser->type > PORT_MAX_8250 || ser->type == PORT_CIRRUS || ser->type == PORT_STARTECH) return -EINVAL; return 0; } static const char * serial8250_type(struct uart_port *port) { int type = port->type; if (type >= ARRAY_SIZE(uart_config)) type = 0; return uart_config[type].name; } static struct uart_ops serial8250_pops = { .tx_empty = serial8250_tx_empty, .set_mctrl = serial8250_set_mctrl, .get_mctrl = serial8250_get_mctrl, .stop_tx = serial8250_stop_tx, .start_tx = serial8250_start_tx, .stop_rx = serial8250_stop_rx, .enable_ms = serial8250_enable_ms, .break_ctl = serial8250_break_ctl, .startup = serial8250_startup, .shutdown = serial8250_shutdown, .set_termios = serial8250_set_termios, .pm = serial8250_pm, .type = serial8250_type, .release_port = serial8250_release_port, .request_port = serial8250_request_port, .config_port = serial8250_config_port, .verify_port = serial8250_verify_port, }; static struct uart_8250_port serial8250_ports[UART_NR]; static void __init serial8250_isa_init_ports(void) { struct uart_8250_port *up; static int first = 1; int i; if (!first) return; first = 0; for (i = 0, up = serial8250_ports; i < ARRAY_SIZE(old_serial_port); i++, up++) { up->port.iobase = old_serial_port[i].port; up->port.irq = old_serial_port[i].irq; up->port.uartclk = get_au1x00_uart_baud_base(); up->port.flags = old_serial_port[i].flags; up->port.hub6 = old_serial_port[i].hub6; up->port.membase = old_serial_port[i].iomem_base; up->port.iotype = old_serial_port[i].io_type; up->port.regshift = old_serial_port[i].iomem_reg_shift; up->port.ops = &serial8250_pops; } } static void __init serial8250_register_ports(struct uart_driver *drv) { int i; serial8250_isa_init_ports(); for (i = 0; i < UART_NR; i++) { struct uart_8250_port *up = &serial8250_ports[i]; up->port.line = i; up->port.ops = &serial8250_pops; init_timer(&up->timer); up->timer.function = serial8250_timeout; /* * ALPHA_KLUDGE_MCR needs to be killed. */ up->mcr_mask = ~ALPHA_KLUDGE_MCR; up->mcr_force = ALPHA_KLUDGE_MCR; uart_add_one_port(drv, &up->port); } } #ifdef CONFIG_SERIAL_AU1X00_CONSOLE #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) /* * Wait for transmitter & holding register to empty */ static inline void wait_for_xmitr(struct uart_8250_port *up) { unsigned int status, tmout = 10000; /* Wait up to 10ms for the character(s) to be sent. */ do { status = serial_in(up, UART_LSR); if (status & UART_LSR_BI) up->lsr_break_flag = UART_LSR_BI; if (--tmout == 0) break; udelay(1); } while ((status & BOTH_EMPTY) != BOTH_EMPTY); /* Wait up to 1s for flow control if necessary */ if (up->port.flags & UPF_CONS_FLOW) { tmout = 1000000; while (--tmout && ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0)) udelay(1); } } /* * Print a string to the serial port trying not to disturb * any possible real use of the port... * * The console_lock must be held when we get here. */ static void serial8250_console_write(struct console *co, const char *s, unsigned int count) { struct uart_8250_port *up = &serial8250_ports[co->index]; unsigned int ier; int i; /* * First save the UER then disable the interrupts */ ier = serial_in(up, UART_IER); serial_out(up, UART_IER, 0); /* * Now, do each character */ for (i = 0; i < count; i++, s++) { wait_for_xmitr(up); /* * Send the character out. * If a LF, also do CR... */ serial_out(up, UART_TX, *s); if (*s == 10) { wait_for_xmitr(up); serial_out(up, UART_TX, 13); } } /* * Finally, wait for transmitter to become empty * and restore the IER */ wait_for_xmitr(up); serial_out(up, UART_IER, ier); } static int __init serial8250_console_setup(struct console *co, char *options) { struct uart_port *port; int baud = 9600; int bits = 8; int parity = 'n'; int flow = 'n'; /* * Check whether an invalid uart number has been specified, and * if so, search for the first available port that does have * console support. */ if (co->index >= UART_NR) co->index = 0; port = &serial8250_ports[co->index].port; /* * Temporary fix. */ spin_lock_init(&port->lock); if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); return uart_set_options(port, co, baud, parity, bits, flow); } extern struct uart_driver serial8250_reg; static struct console serial8250_console = { .name = "ttyS", .write = serial8250_console_write, .device = uart_console_device, .setup = serial8250_console_setup, .flags = CON_PRINTBUFFER, .index = -1, .data = &serial8250_reg, }; static int __init serial8250_console_init(void) { serial8250_isa_init_ports(); register_console(&serial8250_console); return 0; } console_initcall(serial8250_console_init); #define SERIAL8250_CONSOLE &serial8250_console #else #define SERIAL8250_CONSOLE NULL #endif static struct uart_driver serial8250_reg = { .owner = THIS_MODULE, .driver_name = "serial", .devfs_name = "tts/", .dev_name = "ttyS", .major = TTY_MAJOR, .minor = 64, .nr = UART_NR, .cons = SERIAL8250_CONSOLE, }; int __init early_serial_setup(struct uart_port *port) { serial8250_isa_init_ports(); serial8250_ports[port->line].port = *port; serial8250_ports[port->line].port.ops = &serial8250_pops; return 0; } /** * serial8250_suspend_port - suspend one serial port * @line: serial line number * @level: the level of port suspension, as per uart_suspend_port * * Suspend one serial port. */ void serial8250_suspend_port(int line) { uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port); } /** * serial8250_resume_port - resume one serial port * @line: serial line number * @level: the level of port resumption, as per uart_resume_port * * Resume one serial port. */ void serial8250_resume_port(int line) { uart_resume_port(&serial8250_reg, &serial8250_ports[line].port); } static int __init serial8250_init(void) { int ret, i; printk(KERN_INFO "Serial: Au1x00 driver\n"); for (i = 0; i < NR_IRQS; i++) spin_lock_init(&irq_lists[i].lock); ret = uart_register_driver(&serial8250_reg); if (ret >= 0) serial8250_register_ports(&serial8250_reg); return ret; } static void __exit serial8250_exit(void) { int i; for (i = 0; i < UART_NR; i++) uart_remove_one_port(&serial8250_reg, &serial8250_ports[i].port); uart_unregister_driver(&serial8250_reg); } module_init(serial8250_init); module_exit(serial8250_exit); EXPORT_SYMBOL(serial8250_suspend_port); EXPORT_SYMBOL(serial8250_resume_port); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Au1x00 serial driver\n");